System and method for controlling a wireless network

ABSTRACT

In one embodiment, a method is performed by a wireless station. The method includes receiving from an access point (AP) a request for measurement of at least one link-quality parameter. The method further includes measuring the at least one link-quality parameter to generate a link-quality-parameter measurement. The method also includes determining, for the wireless station, an appropriate wireless-station category of a plurality of wireless-station categories. The plurality of wireless-station categories are defined based at least in part on the link-quality-parameter measurement. In addition, the method includes communicating with the AP in accordance with a transmission schedule corresponding to the plurality of wireless-station categories.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority from, and incorporates byreference the entire disclosure of, U.S. Provisional Patent ApplicationNo. 61/945,496, filed Feb. 27, 2014 and U.S. Provisional PatentApplication No. 61/945,516, filed Feb. 27, 2014.

BACKGROUND

Technical Field

The present disclosure relates generally to network management and moreparticularly, but not by way of limitation, to systems and methods forcontrolling a wireless network.

History Of Related Art

A typical wireless network includes an access point and a set ofwireless stations. Some of the wireless stations may be closer to theaccess point than others (e.g., due to geographic dispersion). Inaddition, some of the wireless stations may be partially obstructedrelative to the access point or be subject to environmental variablessuch as weather, atmospheric conditions, etc. The access point and/orthe wireless stations may be powered by a limited power source such as abattery.

As the access point and the wireless stations communicate, such limitedpower sources may be progressively exhausted. Therefore, it can bebeneficial to reduce power consumption in order to preserve each limitedpower source. However, as a general matter, the access point and thewireless stations cannot reduce power consumption without increasing arisk of transmission failure. For example, if the access point and/orthe wireless stations were to transmit communications using reducedpower levels, many of the communications may not reach their intendeddestinations. Such failures can be a result of geographic dispersion,obstructions, environmental factors, collisions, etc.

SUMMARY OF THE INVENTION

In one embodiment, a method is performed by a wireless station. Themethod includes receiving from an access point (AP) a request formeasurement of at least one link-quality parameter. The method furtherincludes measuring the at least one link-quality parameter to generate alink-quality-parameter measurement. The method also includesdetermining, for the wireless station, an appropriate wireless-stationcategory of a plurality of wireless-station categories. The plurality ofwireless-station categories are defined based at least in part on thelink-quality-parameter measurement. In addition, the method includescommunicating with the AP in accordance with a transmission schedulecorresponding to the plurality of wireless-station categories.

In one embodiment, wireless station includes at least onetransmitting/receiving unit and at least one processing unit. The atleast one transmitting/receiving unit and the at least one processingunit are operable to implement a method. The method includes receivingfrom an access point (AP) a request for measurement of at least onelink-quality parameter. The method further includes measuring the atleast one link-quality parameter to generate a link-quality-parametermeasurement. The method also includes determining, for the wirelessstation, an appropriate wireless-station category of a plurality ofwireless-station categories. The plurality of wireless-stationcategories are defined based at least in part on thelink-quality-parameter measurement. In addition, the method includescommunicating with the AP in accordance with a transmission schedulecorresponding to the plurality of wireless-station categories.

In one embodiment, a computer-program product includes a non-transitorycomputer-usable medium having computer-readable program code embodiedtherein. The computer-readable program code is configured, when executedby at least one processor, to receive from an access point (AP) arequest for measurement of at least one link-quality parameter. Thecomputer-readable program code is further configured, when executed bythe at least one processor, to measure the at least one link-qualityparameter to generate a link-quality-parameter measurement. In addition,the computer-readable program code is configured, when executed by theat least one processor, to determine, for a wireless station, anappropriate wireless-station category of a plurality of wireless-stationcategories. The plurality of wireless-station categories defined basedat least in part on the link-quality-parameter measurement. Thecomputer-readable program code is also configured, when executed by theat least one processor, to communicate with the AP in accordance with atransmission schedule corresponding to the plurality of wireless-stationcategories.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the method and apparatus of the presentinvention may be obtained by reference to the following DetailedDescription when taken in conjunction with the accompanying Drawingswherein:

FIG. 1 illustrates an embodiment of a wireless network;

FIG. 2 illustrates an example of a process for initiating an APpower-saving mode;

FIG. 3 illustrates an example of a process for determining an APpower-saving mode;

FIG. 4 illustrates exemplary operation of an AP power-saving mode;

FIG. 5 illustrates an example of a process for onboarding additionalwireless stations to a wireless network;

FIG. 6A illustrates an example of a process for interacting with anadditional wireless station;

FIG. 6B illustrates an example of a process for interacting with anadditional wireless station;

FIG. 6C illustrates an example of a process for interacting with anadditional wireless station;

FIG. 6D illustrates an example of a process for interacting with anadditional wireless station; and

FIG. 7 depicts an example of a wireless network.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS OF THE INVENTION

In various embodiments, power consumption by access points and wirelessstations can be reduced in a fashion that significantly mitigates a riskof transmission failure due to collisions, environmental variables, andother factors. In a typical embodiment, a wireless access point candefine criteria for categorizing a set of wireless stations servedthereby. The criteria can be based, at least in part, on alink-quality-parameter measurement generated by each wireless station.Thereafter, the wireless access point and/or the wireless stations canuse the categorizations to adapt transmission power levels.

FIG. 1 illustrates an embodiment of a wireless network 100 that can beimplemented, for example, as a basic service set (BSS) of a wireless LAN(WLAN). The wireless network 100 includes an access point (AP) 102 andwireless stations 104(1), 104(2), 104(3), 104(4), 104(5), and 104(6)(collectively, wireless stations 104). Each of the wireless stations 104is typically associated with the AP 102. It should be appreciated thatthe particular wireless stations included within the set of wirelessstations 104 can dynamically change as wireless stations associate ordisassociate with the AP 102. In various embodiments, the AP 102 can beconnected to a standalone router (e.g., via a separate wired or wirelessnetwork) or be an integral component of a router.

The AP 102 generally allows the wireless stations 104 to connect to awide area network such as, for example, the Internet, using one or morewireless communication standards. The one or more wireless communicationstandards implemented by the wireless network 100 can include, but arenot limited to, WLAN (e.g., IEEE 802.11 and related standards, HiperLAN,etc.), Wireless Metropolitan Area Networks (WMAN), Local MultipointDistribution Service (LMDS), Worldwide Interoperability for MicrowaveAccess (WiMAX), and/or the like. For illustrative purposes, exampleswill be provided below relative to WLAN and, more particularly, IEEE802.11 standards. However, it should be appreciated that the principlesdescribed herein are not so limited.

The AP 102 and the wireless stations 104 may each be implemented as acomputing system that is programmed or configured to perform therespective functions described herein. The computing system may includemultiple distinct computers or computing devices. More particularly,each such computing system typically includes a processor (or multipleprocessors) that executes program instructions or modules stored in amemory or other non-transitory computer-readable storage medium. Thevarious functions disclosed herein may be embodied in such programinstructions, although some or all of the disclosed functions mayalternatively be implemented in application-specific circuitry (e.g.,ASICs or FPGAs) of the computing system. Where the computing systemincludes multiple computing devices, these devices may, but need not, beco-located. The results of the disclosed methods and tasks may bepersistently stored by transforming physical storage devices, such assolid state memory chips and/or magnetic disks, into a different state.Further examples of the AP 102 and the wireless stations 104 will bedescribed with respect to FIG. 7.

In a typical embodiment, the AP 102 acts as a master to control thewireless stations 104 and provide access to one or more other networks(e.g., the wide area network mentioned above). The AP 102 cancommunicate with the wireless stations 104 using, for example, acombination of management frames, control frames, and data frames.Management frames are generally used to manage communications within thewireless network 100 and can include, but are not limited to, beaconframes, association request/response frames, disassociation frames, etc.Control frames (e.g. ACK frame and RTS/CTS frames) are typically used tofacilitate exchange of data frames. Data frames can be used, forexample, to convey user data between the AP 102 and the wirelessstations 104.

In a typical embodiment, the AP 102 transmits a beacon frame at aperiodic interval to announce a presence of the wireless network 100.The periodic interval may be referred to herein as a beacon interval. Atime when a beacon frame is sent by the AP 102 may be referred to hereinas a target beacon transmission time (TBTT). The beacon frame caninclude, for example, a timestamp, the beacon interval, and a serviceset identifier (SSID). In general, before data delivery through the AP102 begins, the wireless stations 104 synchronize with the AP 102 basedon the timestamp and associate with the AP 102.

In a normal AP operation mode, the AP 102 typically transmits frames ata normal rate and at a normal power level. The normal rate can bespecified, for example, in a mandatory rate set established at thephysical layer (e.g., by an attached transceiver), by a BSS basic ratesetting, and/or the like. The normal rate and/or the normal power levelcan be varied by type of frame. For example, in the case of managementframes and control frames, the normal power level may be a power leveldeemed sufficient for a given frame, transmitted at the normal rate, tobe successfully received by any wireless station in a coverage area ofthe AP 102. A data frame typically includes a header part and a datapart such that the header part includes information for decoding thedata part. In the case of a data frame, the normal power level may be,for example, a power level deemed sufficient for at least a header partof the data frame, transmitted at the normal rate, to be successfullyreceived by any wireless station in the coverage area. In similarfashion, in a normal station-operation mode, each of the wirelessstations 104 typically transmit frames at a normal rate and at a normalpower level. As with the AP 102, the normal rate of each of the wirelessstations 104 can be specified, for example, in a mandatory rate setestablished at the physical layer (e.g., by an attached transceiver), bya BSS basic rate setting, and/or the like.

Radio frequency (RF) transmission can contribute to a majority of powerconsumption by the AP 102 and the wireless stations 104. In certainembodiments, the AP 102 allows an AP power-saving mode to be used inplace of the normal AP operation mode so that power expended duringtransmissions to the wireless stations 104 can be reduced. Morespecifically, the AP 102 can establish one or more criteria that enablecategorization of the wireless stations 104 into two or more categories.As described in greater detail with respect to the ensuing figures, thecategorization can be carried out by the AP 102, the wireless stations104, another suitable network element in communication with the AP 102and/or one or more of the wireless stations 104, and/or a combinationthereof. In a typical embodiment, the one or more criteria can be basedon a link-quality parameter. In certain embodiments, the wirelessstations 104 can similarly allow station power-saving modes so thatpower expended during transmissions to the AP 102 can also be reduced.

A link-quality parameter may indicate the quality of a communicationlink. In particular embodiments, a link-quality parameter may besuggestive, at least in part, of an amount of transmit power needed fora transmission to reach one or more intended destinations. For example,in certain embodiments, a link margin could be used as a link-qualityparameter. The link margin, often measured in dB, is generally adifference between a given wireless station's sensitivity (i.e., areceived power at which the wireless station would stop working) and anactual received power. A link-quality parameter could also be, forexample, a received channel power indicator (RCPI), a receivedsignal-to-noise indicator (RSNI), a composite of such metrics, and/orthe like.

A link-quality-parameter measurement may refer to information usable toevaluate or assess the quality of a communication link. In some cases, agiven link-quality-parameter measurement may directly provide anevaluation or assessment in the form of a value. In other cases, thegiven link-quality-parameter measurement may include informationsufficient to derive an evaluation or assessment, optionally incombination with other information. For example, if the givenlink-quality parameter were link margin, a link-margin value receivedfrom one of the wireless stations 104 could be a link-quality-parametermeasurement. In many cases, however, the given link-quality parametermay be, for example, a composite of two or more metrics such as linkmargin, RCPI, RSNI, distance from the AP 102, etc. In such cases, thelink-margin value mentioned above, while still constituting alink-quality-parameter measurement, might be combined with other metricsin order to compute an evaluation or assessment of the givenlink-quality parameter. An evaluation or assessment of a givenlink-quality parameter may be referred to as a value of the link-qualityparameter.

For ease of description, FIG. 1 depicts the wireless stations 104 asbeing categorized into either a first category 106(1) or a secondcategory 106(2) (collectively, categories 106). However, it should beappreciated that, in practice, the categories 106 can include two,three, four, or any other number of categories that may be appropriatefor a given implementation and/or an environment of the wirelessstations 104. The first category 106(1) can include, for example, thoseof the wireless stations 104 that may adequately communicate with the AP102 despite relatively low transmit power from the AP 102 (e.g., thewireless stations 104(1), 104(2), 104(3), and 104(4)). The secondcategory 106(2) can include, for example, those of the wireless stations104 that require higher transmit power from the AP 102 (e.g., thewireless stations 104(5) and 104(6)). Although the second category106(2) is illustrated as including those of the wireless stations 104that are geographically furthest from the AP 102, it should beappreciated that this need not be the case. For example, environmentalvariables or obstructions may cause higher transmit power to be neededeven when a distance from the AP 102, by itself, does not justify thatresult.

In operation, the AP 102 is operable to determine the categories 106using the one or more criteria described above. Thereafter, the AP 102can determine an AP power-saving mode based on a quantity and/or makeupof the categories 106. The AP power-saving mode can include, forexample, one or more adapted AP-transmission power levels for each ofthe categories 106. In certain embodiments, each adapted AP-transmissionpower level represents power savings relative to a corresponding normalpower level that would otherwise be used in the normal AP operationmode. In certain other embodiments, at least some of the adaptedAP-transmission power levels may be increased relative to thecorresponding normal power level if it is determined, for example, thateach such increase improves a likelihood of successful datatransmission.

The AP power-saving mode can also include a data-transmission schedulethat is based, at least in part, on the categories 106. In general, thedata-transmission schedule regulates when the wireless stations 104 cantransmit and/or receive frames. For example, for each category of thecategories 106, the data-transmission schedule may include time periodsduring which transmission and/or receipt of frames by wireless stationsof that category is allowed or disallowed. For example, whentransmission is disallowed for a given category, the wireless stationsof that category typically refrain from transmitting at least dataframes. Exemplary operation of the AP 102 and the wireless stations 104will be described in more detail with respect to the ensuing Figures.

FIG. 2 illustrates an example of a process 200 for initiating an APpower-saving mode. In a typical embodiment, the process 200 begins withthe AP 102 operating in the normal AP operation mode as described withrespect to FIG. 1. The process 200 can be triggered, for example,automatically as a result of the AP 102 detecting a need to enter an APpower-saving mode, manually by an administrator, in response toreceiving an instruction from a network element coupled to the AP 102,etc. The process 200 can be implemented by any system that can accessone or more data sources. For example, the process 200, in whole or inpart, can be implemented by one or more of the AP 102 and/or any of thewireless stations 104. The process 200 can also be performed generallyby the wireless network 100. Although any number of systems, in whole orin part, can implement the process 200, to simplify discussion, theprocess 200 will be described in relation to specific components of thewireless network 100.

At block 202, the AP 102 determines a link-quality parameter for use incategorizing the wireless stations 104. The link-quality parameter canbe, for example, link margin, RCPI, RSNI, a composition of same, and/orthe like as described above with respect to FIG. 1. In variousembodiments, the link-quality parameter can be selected from one or moreoptions. For example, in some cases, the link-quality parameter can beselected so as to accommodate a type of information that the wirelessstations 104 are operable to provide and/or measure. In otherembodiments, the link-quality parameter can be a default link-qualityparameter that is used for all categorizations. The link-qualityparameter can also be set by an administrator, a network element incommunication with the AP 102, etc. In various embodiments, the block202 can involve determining either one or multiple link-qualityparameters. To simplify discussion, examples will be provided below inwhich the AP 102 determines a single link-quality parameter.

At block 204, the AP 102 sends a request for measurement of thelink-quality parameter to the wireless stations 104. For example, if thelink-quality parameter were link margin, the request could be atransmission power control (TPC) request according to IEEE 802.11standards. The request can also be a new measurement request that is anextension, for example, of IEEE 802.11 standards. In some cases, theblock 204 can involve the AP 102 broadcasting the request formeasurement to all of the wireless stations 104. In other cases, theblock 204 can involve the AP 102 individually sending the request formeasurement to each of the wireless stations 104 or to each of a subsetthereof. At block 206, the wireless stations 104 receive the request formeasurement.

At block 208, each of the wireless stations 104 generates alink-quality-parameter measurement. In general, the block 208 includesthe wireless stations 104 carrying out the request for measurement toyield the link-quality-parameter measurement. The link-quality-parametermeasurement can take the form of a measurement report. For example, ifthe request for measurement is a TPC request as described above, each ofthe wireless stations 104 may measure link margin based on an actualreceived power for the TPC request. The measurement report could be, forexample, a TPC report that includes the measured link margin.

At block 210, each of the wireless stations 104 transmits thelink-quality-parameter measurement to the AP 102. In some embodiments,each of the wireless stations 104 may additionally save the link-qualityparameter measurement in memory for later use. At block 212, the AP 102receives the link-quality-parameter measurement from each of thewireless stations 104. In various embodiments, the AP 102 may maintaineach link-quality-parameter measurement, for example, in a table or liststored in a memory thereof.

At block 214, the AP 102 determines the categories 106 based, at leastin part, on the received link-quality-parameter measurements. Ingeneral, the categories 106 represent non-overlapping ranges of valuesof the link-quality parameter. As noted above, in some cases thereceived link-quality-parameter measurements may be considered values ofthe link-quality parameter, while in other cases the AP 102 may furtherprocess the received link-quality-parameter measurements to obtain thevalues.

In certain embodiments, the categories 106 can be determined byascertaining categorization criteria. For example, the categorizationcriteria can include information sufficient to identify the boundariesof each of the categories 106. In this manner, the categorizationcriteria can be used to determine, for a given wireless station, towhich of the categories 106 it belongs. In some embodiments, thecategorization criteria can be pre-established and stored, for example,in memory of the AP 102. In these embodiments, the block 214 can includethe AP 102 retrieving the categorization criteria. In other embodiments,the categorization criteria can be generated as part of the block 214 asdescribed below.

For example, in some cases, the AP 102 may pre-establish that the numberof categories 106 should be a particular quantity (e.g., two, three,etc.) but not pre-establish the categorization criteria. In these cases,the AP 102 can associate each of the categories 106 with a range of anumeric scale for the link-quality parameter and the categorizationcriteria can include the boundaries of each such range. The AP 102 canassociate each of the categories 106 with a range of the numeric scalein a variety of fashions. For example, the AP 102 may seek to achieve acertain power-saving target, to distribute the wireless stations 104approximately equally across the categories 106, to distribute thenumeric scale approximately equally across the categories 106, etc. Ifthe categories 106 were to include, for example, two categories asillustrated in FIG. 1, the AP 102 could identify a median value amongall values of the link-quality parameter. According to this example, thesecond category 106(2) could be associated with values of thelink-quality parameter that are less than the median value while thefirst category 106(1) could be associated with values of thelink-quality parameter that are greater than or equal to the medianvalue. In this manner, the median value could serve as thecategorization criteria.

In other cases, the AP 102 may not pre-establish a particular quantityof the categories 106. In these cases, the AP 102 can analyze the valuesof the link-quality parameter to identify clusters. In these cases, eachidentified cluster can serve as the basis for a distinct category of thecategories 106. For example, the AP 102 can define the categories 106such that each identified cluster corresponds to different category. Insimilar fashion to the embodiments described above, the categorizationcriteria can specify the boundaries of each of the categories 106.

In various embodiments, the category identification can be performed bythe AP 102, the wireless stations 104, or both the AP 102 and thewireless stations 104. In embodiments in which the AP 102 performs thecategory identification (instead of or in addition to the wirelessstations 104), the block 214 can included the AP 102 performing thecategory identification. Results of the category identification such as,for example, a category of each of the wireless stations 104, can bestored in memory of the AP 102 for later use (e.g., in the APpower-saving mode). In embodiments in which the wireless stations 104perform the category identification (instead of or in addition to the AP102), the AP 102 can notify the wireless stations 104 of thecategorization criteria as part of block 218 (described in greaterdetail below).

At block 216, the AP 102 determines an AP power-saving mode. The APpower-saving mode typically includes at least one adaptedAP-transmission power level for at least one of the categories 106(i.e., a category-specific AP-transmission power level) and adata-transmission schedule. In some embodiments, the AP power-savingmode can further include an adapted AP-transmission power level for eachwireless station of at least a subset of the wireless stations 104(i.e., a station-specific AP-transmission power level). In theseembodiments, the AP 102 can utilize a corresponding category-specificAP-transmission power level when communicating with all stations of aparticular category of the categories 106 and can utilize acorresponding station-specific AP-transmission power level whencommunicating with a particular wireless station of the wirelessstations 104. In certain embodiments, the data-transmission schedule canbe derived from one or more predefined operation modes. An example ofdetermining the AP power-saving mode will be described with respect toFIG. 3.

Table 1 below illustrates examples of predefined operation modes of theAP 102 that can be used as the basis for the data-transmission scheduledescribed above. For illustrative purposes, Table 1 assumes that thecategories 106 include two categories as depicted in FIG. 1. Althoughany number of time periods may be used, Table 1 lists, for eachpredefined operation mode, two time periods: a first time period (T1)and a second time period (T2). During each time period, transmissionand/or reception of data frames is disallowed for at least one of thecategories 106. When transmission is disallowed for a given category,the wireless stations of that category typically refrain fromtransmitting at least data frames.

TABLE 1 Operation First time period (T1) Second time period (T2) modeCategory 1 Category 2 Category 1 Category 2 1 Transmission and Notransmission; No transmission; Transmission and Reception At least no Noreception of Reception reception of data data frames frames (limitationson reception of other types of frames may also be imposed). 2Transmission and No transmission; Transmission and Transmission andReception At least no Reception Reception reception of data frames(limitations on reception of other types of frames may also be imposed).3 Transmission and No transmission; Reception only Transmission andReception At least no Reception reception of data frames (limitations onreception of other types of frames may also be imposed). 4 Transmissionand Reception only Reception only Transmission and Reception Reception 5Transmission and Reception only Transmission and Transmission andReception Reception Reception 6 Transmission and Reception only Notransmission; Transmission and Reception No reception of Reception dataframes. 7 Transmission and Reception only No transmission; Transmissiononly Reception No reception of data frames

At block 218, the AP 102 notifies the wireless stations 104 of the APpower-saving mode. In various embodiments, the notification can be asingle message or multiple messages. As noted above, in variousembodiments, the category identification can be performed by the AP 102,the wireless stations 104, or both the AP 102 and the wireless stations104. In various embodiments, a format of the notification can vary basedon whether the wireless stations 104 perform the categoryidentification.

In the case of only the AP 102 performing the category identification,the notification at the block 218 can include the AP 102 notifying eachof the wireless stations 104 of the appropriate category. In the case ofthe wireless stations 104 performing the category identification(instead of or in addition to the AP 102), the initiation at the block218 can include the AP 102 notifying each of the wireless stations 104of the categorization criteria so that the wireless stations 104 canidentify the appropriate category (e.g., at block 222 described below).Table 2 below provides an exemplary format for the notification whenonly the AP 102 performs the category identification. Table 3 belowprovides an exemplary format for the notification when the wirelessstations 104 perform the category identification (instead of or inaddition to the AP 102). For illustrative purposes, Table 2 and Table 3utilize IEEE 802.11 standards.

TABLE 2 Field Description/Examples Element ID The notification of APpower-saving (Part 1) mode may use a unique Element ID, for example, outof those reserved in IEEE 802.11 standards. Length Describes a number ofoctets in the (Part 2) information field (i.e. a length of Part 3).Categor- Each category can be assigned a ization ID unique category IDcode. For (Part 3) example, if a recipient wireless station belongs tocategory 1, the category ID could be set to a category ID codecorresponding to category 1.

TABLE 3 Field Description/Examples Element ID The notification of APpower-saving mode may use a unique Element ID, for example, (Part 1) outof those reserved in IEEE 802.11 standards. Length Describes a number ofoctets in the information field (i.e. a length from Part 3 to Part 8).(Part 2) Categorization Criteria For example, if the AP determinescategories based on a median value, the categorization (Part 3) criteriacan be set to the median value or a value equivalent to the medianvalue. Operation Mode Each operation mode can be assigned a unique modecode. For example, if the AP (Part 4) determines to switch to operationmode 1, this field could be set to the mode code corresponding tooperation mode 1. Start Time For example, if it is assumed that thecurrent TBTT, as of when the notification is sent, is (Part 5) TBTT (N),and that operation mode 1 will start from TBTT (N + 1), this field couldbe set to 1. Duration of T1 For example, if a first time period (T1) isconfigured to last two beacon intervals, this field (Part 6) could beset to 2. Duration of T2 For example, if a second time period (T2) isconfigured to last one beacon interval, this (Part 7) field could be setto 1 Number of Counts For example, if the operation mode 1 is configuredto repeat three times, this field could (Part 8) be set to three.

Advantageously, in certain embodiments, radio resources can be savedwhen the AP 102 allows the wireless stations 104 to perform the categoryidentification. In these embodiments, the notification at the block 218can include the AP 102 broadcasting a single message containing thecategorization criteria. By comparison, in certain other embodiments inwhich only the AP 102 performs the category identification, multiple,longer messages may be sent (e.g., an individual message to each of thewireless stations 104 that identifies the appropriate category). In manycases, broadcasting a single message as described above can savesignificant radio resources.

At block 220, the wireless stations 104 receive the notification fromthe AP 102. At block 222, the wireless stations 104 implement the APpower-saving mode. In general, the block 222 encompasses the wirelessstations 104 establishing any necessary configurations, for example, toabide by the data-transmission schedule and follow the AP power-savingmode. In addition, as described above, in certain embodiments each ofthe wireless stations 104 may be responsible for identifying theappropriate category of the categories 106. In these embodiments, theimplementation of the AP power-saving mode can include identifying theappropriate category based on the categorization criteria. The wirelessstations 104 can store a result of the category identification such as,for example, an identifier for the appropriate category, in memorythereof for later use (e.g., in the AP power-saving mode). The wirelessstations 104 may send a confirmation message to the AP 102 after theappropriate category has been identified. In some embodiments, the AP102 may treat any of the wireless stations 104 for which no confirmationmessage is received as not supporting the AP power-saving mode. In theseembodiments, such wireless stations may be disassociated from the AP102, forced to enter an idle mode, and/or the like. In variousembodiments, this functionality can be beneficial for backwardscompatibility.

At block 224, the wireless stations 104 can each determine any stationpower-saving mode that may be utilized in conjunction with the APpower-saving mode. For example, each of the wireless stations 104 mayderive an adapted station-transmission power level for use whentransmitting data frames to the AP 102. Each adaptedstation-transmission power level usually represents power savingsrelative to a corresponding normal power level that would otherwise beused in the normal station-operation mode of the wireless stations 104.Each adapted station-transmission power level can be particularizedaccording to the appropriate category of the categories 106, acorresponding link-quality parameter measurement, etc. In certainembodiments, the block 224 may be omitted so that no station-powersaving modes are determined. In these embodiments, it may be deemedsufficient for the wireless stations 104 to follow the AP power-savingmode and otherwise operate normally using, for example, normal powerlevels.

At block 226, the AP 102 and the wireless stations 104 communicate inaccordance with the AP power-saving mode and any applicable stationpower-saving mode. An example of the communication will be describedwith respect to FIG. 4. The block 226 can include, for example, the AP102 and the wireless stations 104 switching back to the normal APoperation mode according to the data-transmission schedule.

FIG. 3 illustrates an example of a process 300 for determining an APpower-saving mode using one or more predefined operation modes. In someembodiments, the process 300 can be performed as all or part of theblock 216 of FIG. 2. The process 300 can be implemented by any systemthat can access one or more data sources. For example, the process 300,in whole or in part, can be implemented by one or more of the AP 102and/or any of the wireless stations 104. The process 300 can also beperformed generally by the wireless network 100. Although any number ofsystems, in whole or in part, can implement the process 300, to simplifydiscussion, the process 300 will be described in relation to specificcomponents of the wireless network 100.

At block 302, the AP 102 determines a predefined operation mode. Thepredefined operation mode can be, for example, one of the predefinedoperation modes listed in Table 1 above. In various embodiments, thepredefined operation mode can be selected based on criteria such as, forexample, a number of the categories 106, the link-quality-parametermeasurements, values of the link-quality parameter, an urgency ofimplementing power savings on the AP 102, a traffic status on thewireless network 100, a distribution of the wireless stations 104 amongthe categories 106, etc. In other embodiments, the determined predefinedoperation mode can be a default operation mode.

At block 304, the AP 102 determines a length of each of a plurality oftime periods. For example, the AP 102 can use one or more criteria tocalculate the length of each of the plurality of time periods. Forexample, the AP 102 could allocate a longer time period to the firstcategory 106(1) if power savings is deemed critical for the AP. The AP102 could also allocate a longer time period to whichever category ofthe categories 106 has a largest proportion of the wireless stations104. By way of further example, the AP 102 could allocate a longer timeperiod to whichever category of the categories 106 has more activetraffic.

In a typical embodiment, the AP 102 can set the length of each of theplurality of time periods in terms of a number of time units, a numberof beacon intervals, or in any other suitable manner. For example, inthe case of beacon intervals, the first time period (T1) could start atTBTT(N+1) and last for two beacon intervals and the second time period(T2) could start from TBTT(N+3) and last for one beacon interval. Thispattern of time period allocation could repeat a desired number of times(e.g., until the number of counts shown in Table 3 is reached). Itshould be understood that the pattern of time period allocation may bealternatively configured in any number of fashions. By way of furtherexample, in the case of time units, the first time period (T1) couldstart at the end of a beacon transmission corresponding to TBTT(N+1) andlast for X time units. Continuing this example, the second time period(T2) could start at the end of the first time period (T1) and last for aduration defined by a difference between the length of a beacon intervaland X.

At block 306, the AP 102 determines adapted AP-transmission powerlevels. As described above with respect to the block 214 of FIG. 2, incertain embodiments the categorization criteria for the categories 106can be pre-established and stored, for example, in memory of the AP 102.In some cases, the adapted AP-transmission power levels can also bepre-established and stored in memory of the AP 102. In theseembodiments, the block 306 can include retrieving the pre-establishedadapted AP-transmission power levels. In other embodiments, the AP 102can determine the adapted AP-transmission power levels throughcomputation as described below.

For example, as described with respect to FIG. 2, the AP 102 can computea category-specific AP-transmission level for each of the categories106, a station-specific AP-transmission level for all or a portion ofthe wireless stations 104, etc. The AP 102 may determine a given adaptedAP-transmission power level in different ways. Equation 1 belowillustrates an example of one such way.A _(P) =N _(p) −L _(m) +B  Equation 1

According to Equation 1, an adapted AP-transmission power level (A_(P))can be computed as a function of a normal AP-transmission power level(N_(p)), a link margin (L_(m)), and a buffer value (B). The normalAP-transmission power level (N_(p)) generally corresponds to whatevernormal power level would be utilized in the situation at hand accordingto the normal AP operation mode. The link margin (L_(m)) is typically alimiting factor with respect to a purpose of the adapted AP-transmissionpower level (A_(P)). In other words, the link margin (L_(m)) can beindicative of an amount by which the normal AP-transmission power level(N_(p)) can potentially be reduced. The buffer value (B) is generally aconfigurable value, greater than or equal to zero, that can be used insome cases to provide additional margin for error. In many cases, thebuffer value (B) may be omitted.

An example of Equation 1 will now be described. As described above, thefirst category 106(1) can include those of the wireless stations 104that require lower transmit power from the AP 102 while the secondcategory 106(2) can include those of the wireless stations 104 thatrequire higher transmit power from the AP 102. As one example of thecomputation, assume that a categorization criterion for the categories106 is a median link-margin value across the wireless stations 104 suchthat the AP 102 has categorized those of the wireless stations 104having a link margin above the median link-margin value into the firstcategory 106(1). In this case, when the AP 102 computes acategory-specific AP-transmission power level for transmissions to thewireless stations of the first category 106(1), the link margin (L_(m))can be set to the median link-margin value and the normalAP-transmission power level (N_(p)) can be set to whatever normal powerlevel would otherwise be used in the normal AP operation mode.Continuing this example, when the AP 102 computes a category-specificAP-transmission power level for transmissions to the wireless stations104 of the second category 106(2), the link margin (L_(m)) can be set tothe smallest link-margin value among those reported by the wirelessstations 104 and the normal AP-transmission power level (N_(p)) can beset to whatever normal power level would otherwise be used in the normalAP operation mode. Alternatively, the AP 102 can determine to use thenormal AP-transmission power level (N_(p)) for transmissions to thewireless stations of the second category 106(2).S _(P) =N _(sp) −L _(m) +B  Equation 2

Equation 2 above illustrates a similar calculation that can be used byeach the wireless stations 104 to calculate an adaptedstation-transmission power level as described with respect to the block224 of FIG. 2. For example, when one of the wireless stations 104computes its adapted station-transmission power level (S_(P)), a linkmargin (L_(m)) can be set to its measured link-margin value (e.g., asgenerated at the block 208 of FIG. 2) and a normal station-transmissionpower level (N_(sp)) can be set to whatever normal power level wouldotherwise be used in the normal station-operation mode.

FIG. 4 illustrates exemplary operation of an AP power-saving mode. Forillustrative purposes, FIG. 4 will be described with respect to thewireless network 100 of FIG. 1. In particular, FIG. 4 depicts operationmode 1 as shown in Table 1 above. Accordingly, during the first timeperiod (T1), those of the wireless stations 104 that are in the firstcategory 106(1) are allowed to transmit and receive frames. Transmissionand receipt of frames by those of the wireless stations 104 that are inthe second category 106(2) are disallowed during the first time period(T1). Therefore, as illustrated, those of the wireless stations 104 thatare in the second category 106(2) refrain from transmitting at leastdata frames during the first time period (T1). During the second timeperiod (T2), those of the wireless stations 104 that are in the secondcategory 106(2) are allowed to transmit and receive frames. Transmissionand receipt of frames by those of the wireless stations 104 that are inthe first category 106(1) are disallowed during the second time period(T2). Therefore, as illustrated, those of the wireless stations 104 thatare in the first category 106(1) refrain from transmitting at least dataframes during the second time period (T2).

A variety of exemplary transmission power levels are shown in FIG. 4.Specifically, P0, P0′, P1D, and P2D are shown to be adaptedAP-transmission power levels. In the illustrated embodiment, P0 is apower level deemed sufficient for a given frame to be successfullyreceived by any wireless station in a coverage area of the AP 102. P0may be, for example, a normal power level as would be used in the normaloperation mode of the AP 102. P0′ may be considered a category-specificAP-transmission level for the first category 106(1). More particularly,P0′ can be a power level deemed sufficient for a given management frame(e.g., beacon frame) to be successfully received by any wireless stationof the first category 106(1).

P1D and P2D are illustrative of category-specific AP-transmission levelsfor the first category 106(1) and the second category 106(2),respectively. In particular, P1D and P2D can be power levels deemedsufficient for a given data frame to be successfully received by anywireless station of the first category 106(1) and the second category106(2), respectively. For example, P1D and P2D can be power levelsdeemed sufficient for at least a header part of data frames to bereceived by wireless stations of the respective category for purposes ofdecoding a data part of the data frames.

P1Ui and P2Ui are each arrays of adapted station-transmission powerlevels. P1Ui and P2Ui correspond to the first category 106(1) and thesecond category 106(2), respectively. Each wireless station of the firstcategory 106(1) has a corresponding adapted station-transmission powerlevel in P1Ui. In like fashion, each wireless station of the secondcategory 106(2) has a corresponding adapted station-transmission powerlevel in P2Ui. In some cases, all station-transmission power levels inthe P1Ui and P2Ui may be equal such that there is, in effect, a singlestation-transmission power level for the first category 106(1) and asingle station-transmission power level for the second category 106(2).In other cases, each adapted station-transmission power level can bestation-specific in the manner described with respect to the block 224above.

A data-transmission schedule of FIG. 4 is summarized by Table 4 below.Based on Table 4, the AP power-saving mode begins at TBTT(N+1), a firsttime period (T1) should last two beacon intervals, and a second timeperiod (T2) should last one beacon interval. The duration of the firsttime period (T1) and the duration of the second time period (T2) canform a data-transmission pattern, which pattern is repeated three timesaccording to a specified number of counts. Exemplary operation duringthe first time period (T1) according to the embodiment illustrated byFIG. 4 will now be described.

TABLE 4 Next Start Time TBTT Duration of T1 2 Duration of T2 1 Number ofCounts 3

In general, during the first time period (T1), the AP 102 can transmitany management frames (e.g., beacon frames) and control frames at thepower level P₀′. In some embodiments, the AP 102 may alternativelytransmit management and control frames at the power level P₀ so that allwireless stations that may be in the coverage area of the AP 102 cansuccessfully receive such frames. The AP 102 transmits any downlink dataframes (D) to the wireless stations of the first category 106(1) at thepower level P_(1D). In similar fashion, during the first time period(T1), the wireless stations of the first category 106(1) can transmituplink data frames (U) to the AP 102 at the reduced power levelsrepresented by P_(1Ui). In some embodiments, any frames intended for thewireless stations of the second category 106(2) may be buffered duringthe first time period (T1). In other embodiments, such frames may bediscarded. In these embodiments, additional power savings can beachieved by eliminating any need to service the wireless stations of thesecond category 106(2) during the first time period (T1).

During the first time period (T1), the AP 102 can realize power savingseach time a management or control frame is transmitted at the powerlevel P₀′ and each time a downlink data frame (D) is sent at the powerlevel P_(1D). In a typical embodiment, the power level P₀′ and the powerlevel P_(1D) represent reductions relative to corresponding normal powerlevels of the normal AP operation mode. However, in a typicalembodiment, a risk of collisions during the first time period (T1) isnot increased. Rather, as the power level P₀′ and the power level P_(1D)are defined above, all frames transmitted by the AP 102 during the firsttime period (T1) will generally be successfully received by the wirelessstations of the first category 106(1). Because, for purposes of thisexample, the wireless stations of the second category 106(2) are notpermitted to transmit frames during the first time period (T1), the factthat some or all of the wireless stations of the second category 106(2)may not detect such frames does not generally impact a risk ofcollisions. Even if collision problems do arise, the collision problemscan be resolved using, for example, control frames (e.g., RTS, CTS, ACK,etc.).

In various embodiments, the wireless stations of the first category106(1) can realize power savings during the time period (T1), forexample, each time an uplink data frame (U) is transmitted using thepower levels P_(1Ui). Since the wireless stations of the second category106(2) are not permitted to transmit frames during the first time period(T1), the wireless stations of the second category 106(2) can realizepower savings, for example, by being in a power-saving or sleep modeaccording to IEEE 802.11 standards for all or part of the first timeperiod (T1). In addition, although the wireless stations of the firstcategory 106(1) utilize the power levels P_(1Ui), a risk of collisionsis not generally increased as result because the wireless stations ofthe second category 106(2) are not permitted to transmit frames duringthe first time period (T1). Rather, as the power levels P_(1Ui) aredefined above, all frames transmitted by the wireless stations of thefirst category 106(1) during the first time period (T1) will generallybe successfully received by the AP 102. As noted above, any collisionproblems that do arise can be resolved using control frames.

Exemplary operation during the second time period (T2) according to theembodiment illustrated by FIG. 4 will now be described. In general,during the second time period (T2), the AP 102 can transmit managementframes (e.g., beacon frames) and control frames at the power level P₀.The AP 102 transmits, at the power level P_(2D), downlink data frames(D) to the wireless stations of the second category 106(2). In similarfashion, during the second time period (T2), the wireless stations ofthe second category 106(2) can transmit uplink data frames (U) to the AP102 at the power levels represented by P_(2Ui). In some embodiments, anyframes intended for the wireless stations of the first category 106(1)may be buffered during the second time period (T2). In otherembodiments, such frames may be discarded. In these embodiments,additional power savings can be achieved by eliminating any need toservice the wireless stations of the first category 106(1) during thesecond time period (T2).

As noted above, the power levels represented by P_(2Ui) may, but neednot be, less than corresponding normal power levels that would otherwisebe used in the normal station-operation mode of the wireless stations ofthe second category 106(2). To the extent that the power levelsrepresented by P_(2Ui) represent reductions, the wireless stations ofthe second category 106(2) can realize power savings during the secondtime period (T2). In addition, since the wireless stations of the firstcategory 106(1) are not permitted to transmit frames during the secondtime period (T2), the wireless stations of the first category 106(1) canrealize power savings, for example, by being in a power-saving or sleepmode according to IEEE 802.11 standards for all or part of the secondtime period (T2). In addition, although the wireless stations of thesecond category 106(2) utilize the power levels P_(2Ui), a risk ofcollisions is not generally increased as result because the wirelessstations of the first category 106(1) are not permitted to transmitframes during the second time period (T2). Rather, as the power levelsP_(2Ui) are defined above, all frames transmitted by the wirelessstations of the second category 106(2) during the second time period(T2) will generally be successfully received by the AP 102. As notedabove, any collision problems that do arise can be resolved usingcontrol frames.

More particularly addressing the embodiment of FIG. 4, at TBTT(N), theAP 102 sends, at the power level P₀, a notification of the APpower-saving mode. In a typical embodiment, utilization of the powerlevel P₀ can help ensure that all of the wireless stations 104successfully receive the notification. The notification may include, forexample, any of the information described with respect to the block 218of FIG. 2. For purposes of this example, the notification is assumed toindicate, inter alia, that the AP power-saving mode will begin atTBTT(N+1). The notification may be sent as part of, or in conjunctionwith, a beacon frame at the time TBTT(N).

A first iteration of the first time period (T1) begins at TBTT(N+1) andcontinues until TBTT(N+3). At TBTT (N+1), the AP 102 transmits a firstbeacon frame at the power level P0′. At time TBTT(N+2), the AP 102transmits a second beacon frame at the power level P0′ in similarfashion to the first beacon frame. Throughout the first iteration of thefirst time period (T1), the AP 102 transmits management and controlframes at the power level P0′ and downlink data frames (D) at the powerlevel P1D. Meanwhile, the wireless stations of the first category 106(1)transmit uplink data frames (U) according to the power levels P1Ui.

A first iteration of the second time period (T2) begins at TBTT(N+3) andcontinues until TBTT(N+4). At TBTT(N+3), the AP 102 transmits a thirdbeacon frame at the power level P0. Throughout the first iteration ofthe second time period (T2), the AP 102 transmits management and controlframes at the power level P0 and downlink data frames (D) at the powerlevel P2D. Meanwhile, the wireless stations of the second category106(2) transmit uplink data frames (U) according to the power levelsP2Ui.

As illustrated in FIG. 4, the wireless network 100 iterates through theabove-described pattern of time-period allocation between the first timeperiod (T1) and the second time period (T2) three times (i.e., inaccordance with the number of counts shown in Table 4). At TBTT (N+10),the AP power-saving mode ends. At this point, the AP 102 and thewireless stations 104 may revert back to their respective normaloperation modes described above.

In various embodiments, the embodiment of FIG. 4 can provide numerousother advantages. For example, in various embodiments, each instance ofa reduced power level described above can serve to reduce interferencewith neighboring wireless networks. To the extent all such wirelessnetworks utilize power-saving modes such as those described above,overall interference among numerous wireless networks can be reduced.Interference can be further reduced because data-transmission schedulessuch as those described above can reduce a total number of wirelessstations that are able to transmit frames at a given time.

It should be appreciated that the embodiment of FIG. 4 is only intendedas an illustrative example of how the AP 102 and the wireless stations104 can operate in an AP power-saving mode. Numerous variations arecontemplated and will be apparent to one of ordinary skill in the artafter reviewing the inventive principles contained herein. For example,the pattern of time period allocation described above could be changedso that the first time period (T1) and the second time period (T2) areequal and, together, take up a beacon interval.

In addition, although the embodiment of FIG. 4 depicts the predefinedoperation mode 1 as shown in Table 1 above, other operation modes canalso be used such as, for example, any of the other predefined operationmodes shown in Table 1. The AP 102 and the wireless stations 104 cantake similar actions depending on a number of time periods, a length ofeach time periods, which categories of wireless stations can receive ortransmit frames in a given time period, which adapted power levels areutilized, etc. For instance, whenever wireless stations of a givencategory are permitted to receive data frames, each transmission by theAP 102 to those wireless stations can be at an adapted AP-transmissionpower level that is, for example, station-specific or category-specific.Whenever wireless stations of a given category are permitted to transmitdata frames, such transmissions can be at an adaptedstation-transmission power level. In similar fashion, the AP 102 cantransmit, for example, management frames and control frames at a powerlevel that is adapted to a desired scope (e.g., all of the wirelessstations 104, one or more particular categories of the categories 106,etc.)

FIG. 5 illustrates an example of a process 500 for onboarding additionalwireless stations to a wireless network. In various embodiments, theprocess 500 can be performed subsequent to the process 200 of FIG. 2.The process 500 can also be performed independently of the process 200of FIG. 2. The process 500 can be implemented by any system that canaccess one or more data sources. For example, the process 500, in wholeor in part, can be implemented by one or more of the AP 102 and/or anyof the wireless stations 104. The process 500 can also be performedgenerally by the wireless network 100. Although any number of systems,in whole or in part, can implement the process 500, to simplifydiscussion, the process 500 will be described in relation to specificcomponents of the wireless network 100.

At block 502, the AP 102 transmits a management frame at a normal powerlevel. In a typical embodiment, the AP 102 is operating in an APpower-saving mode such as, for example, the AP power-saving modedescribed with respect to FIG. 3. In some embodiments, the managementframe may instead be transmitted at an adapted AP-transmission powerlevel. The management frame typically includes a notification of the APpower-saving mode. The management frame can be, for example, a beaconframe. Table 5 and Table 6 illustrate exemplary formats for themanagement frame.

TABLE 5 Field Description/Examples Element ID The notification of APpower-saving mode may use a unique Element ID, for example, (Part 1) outof those reserved in IEEE 802.11 standards. Length Describes a number ofoctets in the information field (i.e. a length from Part 3 to Part 7).(Part 2) Operation Mode Each operation mode can be assigned a uniquemode code. For example, if the AP is (Part 3) operating in operationmode 1, this field could be set to the mode code corresponding tooperation mode 1. Duration of T1 For example, if a first time period(T1) is configured to last two beacon intervals, this field (Part 4)could be set to 2. Duration of T2 For example, if a second time period(T2) is configured to last one beacon interval, this (Part 5) fieldcould be set to 1 Current Time Period Each time period can be assigned aunique period code. For example, if the AP is (Part 6) currentlyoperating in the first time period (T1), this field could be set to 1.Duration Remaining For example, if the AP has finished one beaconinterval of the first time period (T1) and for Current Time the firsttime period (T1) has a duration of two beacon intervals, this fieldcould be set to Period 1. (Part 7)

TABLE 6 Field Description/Examples Element ID The notification of APpower-saving mode may use a unique Element ID, for example, (Part 1) outof those reserved in IEEE 802.11 standards. Length Describes a number ofoctets in the information field (i.e. a length from Part 3 to Part 9).(Part 2) Operation Mode Each operation mode can be assigned a uniquemode code. For example, if the AP is (Part 3) currently operating inoperation mode 1, this field could be set to the mode code correspondingto operation mode 1. Duration of T1 For example, if a first time period(T1) is configured to last two beacon intervals, this field (Part 4)could be set to 2. Duration of T2 For example, if a second time period(T2) is configured to last one beacon interval, this (Part 5) fieldcould be set to 1 Current Time Period Each time period can be assigned aunique period code. For example, if the AP is (Part 6) currentlyoperating in the first time period (T1), this field could be set to 1.Duration Remaining For example, if the AP has finished one beaconinterval of the first time period (T1) and for Current Time the firsttime period (T1) has a duration of two beacon intervals, this fieldcould be set to Period 1. (Part 7) Measurement Request Each link-qualityparameter can be assigned a unique parameter code. For example, if the(Part 8) AP is configured to use link margin as the link-qualityparameter, this field can be set to a link-quality-parameter codecorresponding to link margin. By way of further example, part 8 mayinclude a measurement request such as, for example, a TPC request asdefined in IEEE 802.11 standards, a new measurement request defined asan extension to IEEE 802.11 standards, etc. Categorization Criteria Forexample, if the AP determines categories based on a median value, thecategorization (Part 9) criteria can be set to the median value or avalue equivalent to the median value.

At block 504, the AP 102 interacts with an additional wireless stationto identify an appropriate wireless category of the categories 106.Examples of the interaction will be described with respect to FIGS.6A-6D. At block 506, the AP 102 communicates with the wireless station,in accordance with the AP power-saving mode, as one of the wirelessstations 104.

FIG. 6A illustrates an example of a process 600 a for interacting withan additional wireless station for purposes of onboarding the additionalwireless station to a wireless network. In various embodiments, theprocess 600 a can be performed as all or part of the block 504 of FIG.5. The process 600 a can be implemented by any system that can accessone or more data sources. For example, the process 600 a, in whole or inpart, can be implemented by one or more of the AP 102 and/or any of thewireless stations 104. The process 600 a can also be performed generallyby the wireless network 100. Although any number of systems, in whole orin part, can implement the process 600 a, to simplify discussion, theprocess 600 a will be described in relation to specific components ofthe wireless network 100.

At block 602 a, the additional wireless station sends an associationrequest to the AP 102 for purposes of joining the wireless network 100.The association request is typically responsive to a management framesuch as, for example, the management frame transmitted at the block 502of FIG. 5. For purposes of the process 600 a, the management frame thatis transmitted at the block 502 of FIG. 5 is typically of the form shownin Table 5. The association request can be, for example, according to aformat as defined in IEEE 802.11 standards. The association requesttypically includes a capabilities indication that is indicative of theadditional wireless station's ability to operate in the AP power-savingmode. In some embodiments, the AP 102 may reject the association requestif the additional wireless station fails to indicate that it is capableof operating in the AP power-saving mode.

At block 604 a, the AP 102 receives the association request. At block606 a, the AP 102 sends to the additional wireless station anassociation response (e.g., according to a format as defined in IEEE802.11 standards). The association response includes a request formeasurement of a link-quality parameter that serves as a basis forcategorization in the AP power-saving mode. In various embodiments, theassociation response can be either a single message or multiplemessages. At block 608 a, the additional wireless station receives theassociation response. At block 610 a, the additional wireless stationgenerates a link-quality-parameter measurement. In general, the block610 a can include performing any of the functionality described abovewith respect to the block 208 of FIG. 2.

At block 612 a, the AP 102 receives the link-quality-parametermeasurement. At block 614 a, the AP 102 identifies an appropriatecategory of the categories 106 for the additional wireless station. Theidentification can be based, at least in part, on the receivedlink-quality-parameter measurement and categorization criteriamaintained by the AP 102. In general, the identification of theappropriate category can be performed as described above with respect toFIGS. 1-2. At block 616 a, the AP 102 notifies the additional wirelessstation of the appropriate category. At block 618 a, the additionalwireless station receives the notification. At this point, theadditional wireless station can be associated with the AP 102 and made apart of the wireless stations 104.

FIG. 6B illustrates an example of a process 600 b for interacting withan additional wireless station for purposes of onboarding the additionalwireless station to a wireless network. In various embodiments, theprocess 600 b can be performed as all or part of the block 504 of FIG.5. The process 600 b can be implemented by any system that can accessone or more data sources. For example, the process 600 b, in whole or inpart, can be implemented by one or more of the AP 102 and/or any of thewireless stations 104. The process 600 b can also be performed generallyby the wireless network 100. Although any number of systems, in whole orin part, can implement the process 600 b, to simplify discussion, theprocess 600 b will be described in relation to specific components ofthe wireless network 100.

At block 602 b, the additional wireless station sends an associationrequest to the AP 102 for purposes of joining the wireless network 100.The association request is typically responsive to a management framesuch as, for example, the management frame transmitted at the block 502of FIG. 5. For purposes of the process 600 b, the management frame thatis transmitted at the block 502 of FIG. 5 is typically of the form shownin Table 5. The association request can be, for example, according to aformat as defined in IEEE 802.11 standards. The block 602 b cangenerally include any of the functionality described above with respectto the block 602 a of FIG. 6A.

At block 604 b, the AP 102 receives the association request. At block606 b, the AP 102 sends to the additional wireless station anassociation response (e.g., according to a format as defined in IEEE802.11 standards). The association response includes a categorizationrequest. In a typical embodiment, the categorization request indicatesto the additional wireless station that it, rather than the AP 102, willneed to identify an appropriate category of the categories 106. In thatway, the categorization request can include a request for measurementand categorization criteria. An example of a format for thecategorization request is shown below in Table 7. In variousembodiments, the association response can be one message or multiplemessages.

TABLE 7 Field Description/Examples Element ID The notification of APpower-saving mode may use a unique Element ID, for example, (Part 1) outof those reserved in IEEE 802.11 standards. Length Describes a number ofoctets in the information field (i.e. a length from Part 3 to Part 4).(Part 2) Measurement Each link-quality parameter can be assigned aunique parameter code. For example, if the Request (Part 3) AP isconfigured to use link margin as the link-quality parameter, this fieldcan be set to a link-quality-parameter code corresponding to linkmargin. By way of further example, part 8 may include a measurementrequest such as, for example, a TPC request as defined in IEEE 802.11standards, a new measurement request defined as an extension to IEEE802.11 standards, etc. Categorization For example, if the AP determinescategories based on a median value, the categorization Criteria (Part 4)criteria can be set to the median value or a value equivalent to themedian value.

At block 608 b, the additional wireless station receives the associationresponse. At block 610 b, the additional wireless station identifies theappropriate category of the categories 106 based on the categorizationcriteria. In general, the identification of the appropriate category canbe performed as described above with respect to FIGS. 1-2. At block 612b, the additional wireless station transmits a categorization to the AP102. The categorization typically sets forth the appropriate categorythat was identified at the block 610 b. At block 614 b, the AP 102receives the categorization. At this point, the additional wirelessstation can be associated with the AP 102 and made a part of thewireless stations 104.

FIG. 6C illustrates an example of a process 600 c for interacting withan additional wireless station for purposes of onboarding the additionalwireless station to a wireless network. In various embodiments, theprocess 600 c can be performed as all or part of the block 504 of FIG.5. The process 600 c can be implemented by any system that can accessone or more data sources. For example, the process 600 c, in whole or inpart, can be implemented by one or more of the AP 102 and/or any of thewireless stations 104. The process 600 c can also be performed generallyby the wireless network 100. Although any number of systems, in whole orin part, can implement the process 600 c, to simplify discussion, theprocess 600 c will be described in relation to specific components ofthe wireless network 100.

At block 602 c, the additional wireless station sends an associationrequest to the AP 102 for purposes of joining the wireless network 100.The association request is typically responsive to a management framesuch as, for example, the management frame transmitted at the block 502of FIG. 5. For purposes of the process 600 c, the management frame thatis transmitted at the block 502 of FIG. 5 is typically of the form shownin Table 5. However, according to a predefined protocol, the managementframe is treated as an implicit request for measurement of a particularlink-quality parameter. Therefore, for purposes of the example of theprocess 600 c, the association request includes a link-quality-parametermeasurement pursuant to the implicit request for measurement.

At block 604 c, the AP 102 receives the association request. At block606 c, the AP 102 identifies an appropriate category of the categories106 for the additional wireless station. The identification can bebased, at least in part, on the received link-quality-parametermeasurement and categorization criteria maintained by the AP 102. Ingeneral, the identification of the appropriate category can be performedas described above with respect to FIGS. 1-2. At block 608 c, the AP 102sends to the additional wireless station an association response thatincludes a notification of the appropriate category. At block 610 c, thewireless station receives the association response. At this point, theadditional wireless station can be associated with the AP 102 and made apart of the wireless stations 104.

FIG. 6D illustrates an example of a process 600 d for interacting withan additional wireless station for purposes of onboarding the additionalwireless station to a wireless network. In various embodiments, theprocess 600 d can be performed as all or part of the block 504 of FIG.5. The process 600 d can be implemented by any system that can accessone or more data sources. For example, the process 600 d, in whole or inpart, can be implemented by one or more of the AP 102 and/or any of thewireless stations 104. The process 600 d can also be performed generallyby the wireless network 100. Although any number of systems, in whole orin part, can implement the process 600 d, to simplify discussion, theprocess 600 d will be described in relation to specific components ofthe wireless network 100.

At block 602 d, the additional wireless station generates alink-quality-parameter measurement. In a typical embodiment, the block602 d is performed responsive to a management frame such as, forexample, the management frame transmitted at the block 502 of FIG. 5.For purposes of the process 600 d, the management frame that istransmitted at the block 502 of FIG. 5 is typically of the form shown inTable 6. In other words, the management frame generally includes acategorization request of the type described with respect to the block606 b of FIG. 6. Therefore, the block 602 d can include generating thelink-quality-parameter measurement according to a measurement requestcontained within the management frame.

At block 604 d, the additional wireless station identifies anappropriate category of the categories 106 based, at least in part, onthe link-quality-parameter measurement and categorization criteriacontained within the management frame. In general, the identification ofthe appropriate category can be performed as described above withrespect to FIGS. 1-2. At block 606 d, the additional wireless stationsends an association request to the AP 102 for purposes of joining thewireless network 100. For purposes of the example of the process 600 d,the association request includes a categorization for the additionalwireless station. The categorization typically sets forth theappropriate category as identified by the additional wireless station atthe block 604 d. At block 608 d, the AP 102 receives the associationrequest. At this point, the additional wireless station can beassociated with the AP 102 and made a part of the wireless stations 104.

For illustrative purposes, the examples described above with respect toFIGS. 1-6D relate to categorizing wireless stations according to alink-quality parameter for purposes of reducing power consumption whileminimizing collisions. However, it should be appreciated that theprinciples described above can also be used for numerous other purposesother than reducing power consumption.

For example, with reference to FIG. 1, the wireless stations of thesecond category 106(2) may be located near an edge of the wirelessnetwork 100 and easily affected by interference from adjacent wirelessnetworks. In various embodiments, the AP 102 can instruct, for example,the wireless stations of the second category 106(2) to measureinterference from adjacent wireless networks. In many cases, this canreduce a time and power consumption by the wireless stations of thefirst category 106(1). The AP 102 can collect, from the wirelessstations of the second category 106(2), measurement data oninterferences from the adjacent wireless networks. If, for example, theadjacent wireless networks are managed by a same operator as thewireless network 100, the collected measurement data on interferencesfrom the adjacent wireless networks can be sent by the AP 102 to anetwork-management node in the operator's network.

The network-management node can analyze the collected measurement dataand decide to request at least one of the adjacent wireless networks toreduce a maximum-allowed transmit power. In another example, assume thata second wireless network adjacent to the wireless network 100 has asame structure as the wireless network 100 as illustrated with respectto FIG. 1 and has two categories of wireless stations: a first categoryand a second category. The wireless stations of the second category inthe second wireless network may be located near the edge of that networkand be the main contributor to the interference with the wirelessnetwork 100. The AP of the second wireless network can be notified bythe network-management node if the wireless network 100 suffers, forexample, from severe interference. Thereafter, the AP of the secondwireless network could instruct, for example, the wireless stations ofthe second category in the second wireless network to ceasetransmissions for at least a certain time period so as to reduceinterference with the wireless network 100. In this case, the AP of thesecond wireless network can select an operation mode such as operationmode 2 or 5 described in Table 1.

FIG. 7 depicts an example wireless network 700 including an examplewireless station 704(1), an example wireless station 704(2), and anexample access point 702. In general, wireless network 700 can performfunctionality described, for example, with respect to the wirelessnetwork 100 of FIG. 1. For example, the AP 702 can perform functionalitydescribed with respect to the AP 102 of FIG. 1. In like fashion, thewireless station 704(1) and the wireless station 704(2) can each performfunctionality attributed to any of the wireless stations 104 of FIG. 1.For illustrative purposes, the wireless network 700 is shown to includetwo wireless stations: the wireless station 704(1) and the wirelessstation 704(2). As described with respect to the wireless network 100 ofFIG. 1, the wireless network 700 can include any number of wirelessstations.

Wireless station 704(1), wireless station 704(2), and access point 702may each include one or more portions of one or more computer systems.In particular embodiments, one or more of these computer systems mayperform one or more steps of one or more methods described orillustrated herein. In particular embodiments, one or more computersystems may provide functionality described or illustrated herein. Inparticular embodiments, encoded software running on one or more computersystems may perform one or more steps of one or more methods describedor illustrated herein or provide functionality described or illustratedherein.

The components of wireless station 704(1), wireless station 704(2), andaccess point 702 may comprise any suitable physical form, configuration,number, type and/or layout. As an example, and not by way of limitation,wireless station 704(1), wireless station 704(2), and/or access point702 may comprise an embedded computer system, a system-on-chip (SOC), asingle-board computer system (SBC) (such as, for example, acomputer-on-module (COM) or system-on-module (SOM)), a desktop computersystem, a laptop or notebook computer system, an interactive kiosk, amainframe, a mesh of computer systems, a mobile telephone, a personaldigital assistant (PDA), a server, or a combination of two or more ofthese. Where appropriate, wireless station 704(1), wireless station704(2), and/or access point 702 may include one or more computersystems; be unitary or distributed; span multiple locations; spanmultiple machines; or reside in a cloud, which may include one or morecloud components in one or more networks.

In the depicted embodiment, wireless station 704(1), wireless station704(2), and access point 702 each include their own respectiveprocessors 211, 221, and 231; memory 213, 223, and 233; storage 215,225, and 235; interfaces 217, 227, and 237; and buses 219, 229, and 239.Although a particular wireless network is depicted having a particularnumber of particular components in a particular arrangement, thisdisclosure contemplates any suitable wireless network 700 having anysuitable number of any suitable components in any suitable arrangement.For simplicity, similar components of wireless station 704(1), wirelessstation 704(2), and access point 702 will be discussed together whilereferring to the component of wireless station 704(1). However, it isnot necessary for these devices to have the same components, or the sametype of components. For example, processor 211 may be a general purposemicroprocessor and processor 221 may be an application specificintegrated circuit (ASIC).

Processor 211 may be a microprocessor, controller, or any other suitablecomputing device, resource, or combination of hardware, software and/orencoded logic operable to provide, either alone or in conjunction withother components, (e.g., memory 213) wireless networking functionality.Such functionality may include providing various features discussedherein. For example, processor 211 may determine an appropriatewireless-station category as described above. In particular embodiments,processor 211 may include hardware for executing instructions, such asthose making up a computer program. As an example and not by way oflimitation, to execute instructions, processor 211 may retrieve (orfetch) instructions from an internal register, an internal cache, memory213, or storage 215; decode and execute them; and then write one or moreresults to an internal register, an internal cache, memory 213, orstorage 215.

In particular embodiments, processor 211 may include one or moreinternal caches for data, instructions, or addresses. This disclosurecontemplates processor 211 including any suitable number of any suitableinternal caches, where appropriate. As an example and not by way oflimitation, processor 211 may include one or more instruction caches,one or more data caches, and one or more translation lookaside buffers(TLBs). Instructions in the instruction caches may be copies ofinstructions in memory 213 or storage 215 and the instruction caches mayspeed up retrieval of those instructions by processor 211. Data in thedata caches may be copies of data in memory 213 or storage 215 forinstructions executing at processor 211 to operate on; the results ofprevious instructions executed at processor 211 for access by subsequentinstructions executing at processor 211, or for writing to memory 213,or storage 215; or other suitable data. The data caches may speed upread or write operations by processor 211. The TLBs may speed upvirtual-address translations for processor 211. In particularembodiments, processor 211 may include one or more internal registersfor data, instructions, or addresses. Depending on the embodiment,processor 211 may include any suitable number of any suitable internalregisters, where appropriate. Where appropriate, processor 211 mayinclude one or more arithmetic logic units (ALUs); be a multi-coreprocessor; include one or more processors 211; or any other suitableprocessor.

Memory 213 may be any form of volatile or non-volatile memory including,without limitation, magnetic media, optical media, random access memory(RAM), read-only memory (ROM), flash memory, removable media, or anyother suitable local or remote memory component or components. Inparticular embodiments, memory 213 may include random access memory(RAM). This RAM may be volatile memory, where appropriate. Whereappropriate, this RAM may be dynamic RAM (DRAM) or static RAM (SRAM).Moreover, where appropriate, this RAM may be single-ported ormulti-ported RAM, or any other suitable type of RAM or memory. Memory213 may include one or more memories 213, where appropriate. Memory 213may store any suitable data or information utilized by wireless station704(1), including software embedded in a computer readable medium,and/or encoded logic incorporated in hardware or otherwise stored (e.g.,firmware). In particular embodiments, memory 213 may include main memoryfor storing instructions for processor 211 to execute or data forprocessor 211 to operate on. In particular embodiments, one or morememory management units (MMUs) may reside between processor 211 andmemory 213 and facilitate accesses to memory 213 requested by processor211.

As an example and not by way of limitation, wireless station 704(1) mayload instructions from storage 215 or another source (such as, forexample, another computer system) to memory 213. Processor 211 may thenload the instructions from memory 213 to an internal register orinternal cache. To execute the instructions, processor 211 may retrievethe instructions from the internal register or internal cache and decodethem. During or after execution of the instructions, processor 211 maywrite one or more results (which may be intermediate or final results)to the internal register or internal cache. Processor 211 may then writeone or more of those results to memory 213. In particular embodiments,processor 211 may execute only instructions in one or more internalregisters or internal caches or in memory 213 (as opposed to storage 215or elsewhere) and may operate only on data in one or more internalregisters or internal caches or in memory 213 (as opposed to storage 215or elsewhere).

In particular embodiments, storage 215 may include mass storage for dataor instructions. As an example and not by way of limitation, storage 215may include a hard disk drive (HDD), a floppy disk drive, flash memory,an optical disc, a magneto-optical disc, magnetic tape, or a UniversalSerial Bus (USB) drive or a combination of two or more of these. Storage215 may include removable or non-removable (or fixed) media, whereappropriate. Storage 215 may be internal or external to wireless station704(1), where appropriate. In particular embodiments, storage 215 may benon-volatile, solid-state memory. In particular embodiments, storage 215may include read-only memory (ROM). Where appropriate, this ROM may bemask-programmed ROM, programmable ROM (PROM), erasable PROM (EPROM),electrically erasable PROM (EEPROM), electrically alterable ROM (EAROM),or flash memory or a combination of two or more of these. Storage 215may take any suitable physical form and may comprise any suitable numberor type of storage. Storage 215 may include one or more storage controlunits facilitating communication between processor 211 and storage 215,where appropriate.

In particular embodiments, interface 217 may include hardware, encodedsoftware, or both providing one or more interfaces for communication(such as, for example, packet-based communication) among wirelessstation 704(1), wireless station 704(2), access point 702, any networks,any network devices, and/or any other computer systems. As an exampleand not by way of limitation, communication interface 217 may include anetwork interface controller (NIC) or network adapter for communicatingwith an Ethernet or other wire-based network and/or a wireless NIC(WNIC) or wireless adapter for communicating with a wireless network.

In some embodiments, interface 217 comprises one or more radios coupledto one or more physical antenna ports 116. Depending on the embodiment,interface 217 may be any type of interface suitable for any type ofnetwork for which wireless network 700 is used. As an example and not byway of limitation, wireless network 700 can include (or communicatewith) an ad-hoc network, a personal area network (PAN), a local areanetwork (LAN), a wide area network (WAN), a metropolitan area network(MAN), or one or more portions of the Internet or a combination of twoor more of these. One or more portions of one or more of these networksmay be wired or wireless. As an example, wireless network 700 caninclude (or communicate with) a wireless PAN (WPAN) (such as, forexample, a BLUETOOTH WPAN), a WI-FI network, a WI-MAX network, an LTEnetwork, an LTE-A network, a cellular telephone network (such as, forexample, a Global System for Mobile Communications (GSM) network), orany other suitable wireless network or a combination of two or more ofthese. Wireless station 704(1) may include any suitable interface 217for any one or more of these networks, where appropriate.

In some embodiments, interface 217 may include one or more interfacesfor one or more I/O devices. One or more of these I/O devices may enablecommunication between a person and wireless station 704(1). As anexample and not by way of limitation, an I/O device may include akeyboard, keypad, microphone, monitor, mouse, printer, scanner, speaker,still camera, stylus, tablet, touchscreen, trackball, video camera,another suitable I/O device or a combination of two or more of these. AnI/O device may include one or more sensors. Particular embodiments mayinclude any suitable type and/or number of I/O devices and any suitabletype and/or number of interfaces 117 for them. Where appropriate,interface 117 may include one or more drivers enabling processor 211 todrive one or more of these I/O devices. Interface 117 may include one ormore interfaces 117, where appropriate.

Bus 219 may include any combination of hardware, software embedded in acomputer readable medium, and/or encoded logic incorporated in hardwareor otherwise stored (e.g., firmware) to couple components of wirelessstation 704(1) to each other. As an example and not by way oflimitation, bus 219 may include an Accelerated Graphics Port (AGP) orother graphics bus, an Enhanced Industry Standard Architecture (EISA)bus, a front-side bus (FSB), a HYPERTRANSPORT (HT) interconnect, anIndustry Standard Architecture (ISA) bus, an INFINIBAND interconnect, alow-pin-count (LPC) bus, a memory bus, a Micro Channel Architecture(MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express(PCI-X) bus, a serial advanced technology attachment (SATA) bus, a VideoElectronics Standards Association local (VLB) bus, or any other suitablebus or a combination of two or more of these. Bus 219 may include anynumber, type, and/or configuration of buses 219, where appropriate. Inparticular embodiments, one or more buses 219 (which may each include anaddress bus and a data bus) may couple processor 211 to memory 213. Bus219 may include one or more memory buses.

Herein, reference to a computer-readable storage medium encompasses oneor more tangible computer-readable storage media possessing structures.As an example and not by way of limitation, a computer-readable storagemedium may include a semiconductor-based or other integrated circuit(IC) (such, as for example, a field-programmable gate array (FPGA) or anapplication-specific IC (ASIC)), a hard disk, an HDD, a hybrid harddrive (HHD), an optical disc, an optical disc drive (ODD), amagneto-optical disc, a magneto-optical drive, a floppy disk, a floppydisk drive (FDD), magnetic tape, a holographic storage medium, asolid-state drive (SSD), a RAM-drive, a SECURE DIGITAL card, a SECUREDIGITAL drive, a flash memory card, a flash memory drive, or any othersuitable tangible computer-readable storage medium or a combination oftwo or more of these, where appropriate.

Particular embodiments may include one or more computer-readable storagemedia implementing any suitable storage. In particular embodiments, acomputer-readable storage medium implements one or more portions ofprocessor 211 (such as, for example, one or more internal registers orcaches), one or more portions of memory 213, one or more portions ofstorage 215, or a combination of these, where appropriate. In particularembodiments, a computer-readable storage medium implements RAM or ROM.In particular embodiments, a computer-readable storage medium implementsvolatile or persistent memory. In particular embodiments, one or morecomputer-readable storage media embody encoded software.

Herein, reference to encoded software may encompass one or moreapplications, bytecode, one or more computer programs, one or moreexecutables, one or more instructions, logic, machine code, one or morescripts, or source code, and vice versa, where appropriate, that havebeen stored or encoded in a computer-readable storage medium. Inparticular embodiments, encoded software includes one or moreapplication programming interfaces (APIs) stored or encoded in acomputer-readable storage medium. Particular embodiments may use anysuitable encoded software written or otherwise expressed in any suitableprogramming language or combination of programming languages stored orencoded in any suitable type or number of computer-readable storagemedia. In particular embodiments, encoded software may be expressed assource code or object code. In particular embodiments, encoded softwareis expressed in a higher-level programming language, such as, forexample, C, Perl, or a suitable extension thereof. In particularembodiments, encoded software is expressed in a lower-level programminglanguage, such as assembly language (or machine code). In particularembodiments, encoded software is expressed in JAVA. In particularembodiments, encoded software is expressed in Hyper Text Markup Language(HTML), Extensible Markup Language (XML), or other suitable markuplanguage.

Any suitable combination of various embodiments, or the featuresthereof, is contemplated. For example, any of the devices disclosedherein can include features of other embodiments. Thus, AP 102 may haveany of the features described herein with respect to AP 702 and wirelessstation 104 may have any of the features described herein with respectto wireless station 704. As another example, any steps disclosed in amethod herein may be used in other methods described herein. Thus, astep of one of the methods described in FIG. 2, 3, 4, 5, or 6A-6D may beused in any of the methods described in these Figures.

In one embodiment, a method is performed by an access point (AP). Themethod includes sending to at least one of a plurality of wirelessstations a request for measurement of at least one link-qualityparameter, receiving at least one link-quality-parameter measurementfrom the at least one of the plurality of wireless stations, anddetermining a plurality of wireless-station categories based, at leastin part, on the received at least one link-quality-parametermeasurement, the plurality of wireless-station categories including atleast a first category and a second category. The method furtherincludes communicating with the plurality of wireless stations inaccordance with a transmission schedule corresponding to the pluralityof wireless-station categories.

In a typical embodiment, the transmission schedule comprises a firsttime period and the transmission schedule disallows transmission of atleast data frames by each wireless station of the second category duringthe first time period and the communicating comprises, during at least aportion of the first time period, transmitting a frame to a wirelessstation of the first category at an AP-transmission power levelassociated with the first category, the AP-transmission power levelassociated with the first category being distinct from anAP-transmission power level associated with the second category. Themethod further includes determining a length of the first time periodand the transmission schedule comprises a second time period duringwhich transmission of at least data frames by wireless stations of thefirst category is disallowed.

In a typical embodiment, the communicating comprises, during the firsttime period, transmitting a frame to a wireless station of the firstcategory at an AP-transmission power level associated with the firstcategory and the communicating comprises, during the second time period,transmitting a frame to a wireless station of the second category at anAP-transmission power level higher than the AP-transmission power levelassociated with the first category.

In a typical embodiment, the transmission schedule comprises a secondtime period during which transmission and reception of frames bywireless stations of the first category and the second category areallowed.

In a typical embodiment, the communicating comprises, during the firsttime period, transmitting a frame to a wireless station of the firstcategory at an AP-transmission power level associated with the firstcategory and the communicating comprises, during the second time period,transmitting a frame to a wireless station of the first category andtransmitting a frame to a wireless station of the second category at anAP-transmission power level that is higher than the AP-transmissionpower level associated with the first category.

In a typical embodiment, the method further includes determining anadapted AP-transmission power level for each wireless-station categoryof the plurality of wireless-station categories, wherein the adaptedAP-transmission power level determined for the first category isdistinct from the adapted AP-transmission power level determined for thesecond category, and transmitting a frame to a wireless station of thefirst category using the adapted AP-transmission power level. In oneembodiment, the AP-transmission power level associated with the secondcategory is a normal AP-transmission power level that is higher than theAP-transmission power level associated with the first category. Themethod further includes notifying the plurality of wireless stations ofthe transmission schedule and wherein the plurality of wireless-stationcategories are defined by non-overlapping ranges of values of the atleast one link-quality parameter.

In a typical embodiment, the method further includes interacting with anadditional wireless station to identify, for the additional wirelessstation, an appropriate wireless-station category of the plurality ofwireless-station categories and communicating with the additionalwireless station in accordance with the transmission schedule. In atypical embodiment, the at least one link-quality parameter comprises atleast one of a link margin, a channel power indicator, and asignal-to-noise indicator.

In a typical embodiment, the method further includes selecting one ormore wireless-station categories of the plurality of categories, sendinga request to at least one wireless station of at least one of theselected one or more wireless-station categories for an interferencemeasurement, and receiving at least one interference measurement fromthe at least one wireless station. The selected one or morewireless-station categories include wireless stations deemed to bevulnerable to interference based on the link-quality-parametermeasurement.

In a typical embodiment, determining of the plurality ofwireless-station categories includes determining at least onecategorization criterion relative to the at least one link-qualityparameter and via the at least one criterion, identifying an appropriatewireless-station category of the plurality of wireless-stationcategories for each of the plurality of wireless stations. The methodfurther includes for each wireless station of the plurality of wirelessstations, notifying the wireless station of the appropriatewireless-station category.

In a typical embodiment, determining of the plurality ofwireless-station categories includes determining at least onecategorization criterion relative to the at least one link-qualityparameter and notifying the plurality of wireless stations of the atleast one categorization criterion so that each wireless station canidentify an appropriate wireless-station category of the plurality ofwireless-station categories. The determining of the plurality ofwireless-station categories includes via the at least one categorizationcriterion, identifying an appropriate wireless-station category of theplurality of wireless-station categories for each of the plurality ofwireless stations. The determining of the plurality of wireless-stationcategories further comprises includes receiving at least oneconfirmation message from at least one of the plurality of wirelessstations indicating the appropriate wireless-station category of the atleast one of the plurality of wireless stations and saving anappropriate wireless-station category of the plurality ofwireless-station categories for each of the plurality of wirelessstations based on the received at least one confirmation message.

In one embodiment, at least one of the plurality of wireless-stationcategories is assigned at least two of the plurality of wirelessstations.

In one embodiment, an access point (AP) includes atransmitting/receiving unit and at least one processing unit, whereinthe transmitting/receiving unit and the at least one processing unit areoperable to implement a method, the method includes sending to at leastone of a plurality of wireless stations a request for measurement of atleast one link-quality parameter, receiving at least onelink-quality-parameter measurement from the at least one of theplurality of wireless stations, determining a plurality ofwireless-station categories based, at least in part, on the received atleast one link-quality-parameter measurement, the plurality ofwireless-station categories including at least a first category and asecond category, and communicating with the plurality of wirelessstations in accordance with a transmission schedule corresponding to theplurality of wireless-station categories.

In a typical embodiment, the transmission schedule comprises a firsttime period and the transmission schedule disallows transmission of atleast data frames by each wireless station of the second category duringthe first time period and the communicating comprises, during at least aportion of the first time period, transmitting a frame to a wirelessstation of the first category at an AP-transmission power levelassociated with the first category, the AP-transmission power levelassociated with the first category being distinct from anAP-transmission power level associated with the second category.

In a typical embodiment, the method includes determining a length of thefirst time period and the transmission schedule comprises a second timeperiod during which transmission of at least data frames by wirelessstations of the first category is disallowed.

In one embodiment, the communicating includes during the first timeperiod, transmitting a frame to a wireless station of the first categoryat an AP-transmission power level associated with the first category andduring the second time period, transmitting a frame to a wirelessstation of the second category at an AP-transmission power level higherthan the AP-transmission power level associated with the first category.

In a typical embodiment, the transmission schedule comprises a secondtime period during which transmission and reception of frames bywireless stations of the first category and the second category areallowed and the communicating comprises during the first time period,transmitting a frame to a wireless station of the first category at anAP-transmission power level associated with the first category andduring the second time period, transmitting a frame to a wirelessstation of the first category and transmitting a frame to a wirelessstation of the second category at an AP-transmission power level that ishigher than the AP-transmission power level associated with the firstcategory.

In a typical embodiment, the method further includes determining anadapted AP-transmission power level for each wireless-station categoryof the plurality of wireless-station categories, wherein the adaptedAP-transmission power level determined for the first category isdistinct from the adapted AP-transmission power level determined for thesecond category, and transmitting a frame to a wireless station of thefirst category using the adapted AP-transmission power level. TheAP-transmission power level associated with the second category is anormal AP-transmission power level that is higher than theAP-transmission power level associated with the first category.

In a typical embodiment, the method further includes notifying theplurality of wireless stations of the transmission schedule, wherein theplurality of wireless-station categories are defined by non-overlappingranges of values of the at least one link-quality parameter. The methodfurther includes interacting with an additional wireless station toidentify, for the additional wireless station, an appropriatewireless-station category of the plurality of wireless-stationcategories and communicating with the additional wireless station inaccordance with the transmission schedule. The at least one link-qualityparameter includes at least one of a link margin, a channel powerindicator, and a signal-to-noise indicator.

In a typical embodiment, the method further includes selecting one ormore wireless-station categories of the plurality of categories, sendinga request to at least one wireless station of at least one of theselected one or more wireless-station categories for an interferencemeasurement, and receiving at least one interference measurement fromthe at least one wireless station. The selected one or morewireless-station categories include wireless stations deemed to bevulnerable to interference based on the link-quality-parametermeasurement.

In a typical embodiment, the determining of the plurality ofwireless-station categories comprises determining at least onecategorization criterion relative to the at least one link-qualityparameter, via the at least one criterion, identifying an appropriatewireless-station category of the plurality of wireless-stationcategories for each of the plurality of wireless stations, and furtherincluding for each wireless station of the plurality of wirelessstations, notifying the wireless station of the appropriatewireless-station category.

In a typical embodiment, the determining of the plurality ofwireless-station categories comprises determining at least onecategorization criterion relative to the at least one link-qualityparameter and notifying the plurality of wireless stations of the atleast one categorization criterion so that each wireless station canidentify an appropriate wireless-station category of the plurality ofwireless-station categories. The determining of the plurality ofwireless-station categories further includes via the at least onecategorization criterion, identifying an appropriate wireless-stationcategory of the plurality of wireless-station categories for each of theplurality of wireless stations, receiving at least one confirmationmessage from at least one of the plurality of wireless stationsindicating the appropriate wireless-station category of the at least oneof the plurality of wireless stations, and saving an appropriatewireless-station category of the plurality of wireless-stationcategories for each of the plurality of wireless stations based on thereceived at least one confirmation message.

In a typical embodiment, at least one of the plurality ofwireless-station categories is assigned at least two of the plurality ofwireless stations.

In a typical embodiment, computer-program product comprising anon-transitory computer-usable medium having computer-readable programcode embodied therein, the computer-readable program code configured,when executed by at least one processor, to send to at least one of aplurality of wireless stations a request for measurement of at least onelink-quality parameter, receive at least one link-quality-parametermeasurement from the at least one of the plurality of wireless stations,determine a plurality of wireless-station categories based, at least inpart, on the received at least one link-quality-parameter measurement,the plurality of wireless-station categories including at least a firstcategory and a second category, and communicate with the plurality ofwireless stations in accordance with a transmission schedulecorresponding to the plurality of wireless-station categories.

Depending on the embodiment, certain acts, events, or functions of anyof the algorithms described herein can be performed in a differentsequence, can be added, merged, or left out altogether (e.g., not alldescribed acts or events are necessary for the practice of thealgorithms). Moreover, in certain embodiments, acts or events can beperformed concurrently, e.g., through multi-threaded processing,interrupt processing, or multiple processors or processor cores or onother parallel architectures, rather than sequentially. Although certaincomputer-implemented tasks are described as being performed by aparticular entity, other embodiments are possible in which these tasksare performed by a different entity.

Conditional language used herein, such as, among others, “can,” “might,”“may,” “e.g.,” and the like, unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain embodiments include, while other embodiments donot include, certain features, elements and/or states. Thus, suchconditional language is not generally intended to imply that features,elements and/or states are in any way required for one or moreembodiments or that one or more embodiments necessarily include logicfor deciding, with or without author input or prompting, whether thesefeatures, elements and/or states are included or are to be performed inany particular embodiment.

While the above detailed description has shown, described, and pointedout novel features as applied to various embodiments, it will beunderstood that various omissions, substitutions, and changes in theform and details of the devices or algorithms illustrated can be madewithout departing from the spirit of the disclosure. As will berecognized, the processes described herein can be embodied within a formthat does not provide all of the features and benefits set forth herein,as some features can be used or practiced separately from others. Thescope of protection is defined by the appended claims rather than by theforegoing description. All changes which come within the meaning andrange of equivalency of the claims are to be embraced within theirscope.

Although various embodiments of the method and apparatus of the presentinvention have been illustrated in the accompanying Drawings anddescribed in the foregoing Detailed Description, it will be understoodthat the invention is not limited to the embodiments disclosed, but iscapable of numerous rearrangements, modifications and substitutionswithout departing from the spirit of the invention as set forth herein.

What is claimed is:
 1. A method by a wireless station associated with anaccess point (AP) in a wireless network, the method comprising:measuring at least one link-quality parameter based on at least a signalreceived from the AP to generate a link-quality-parameter measurement;receiving, from the AP, a notification comprising at least onewireless-station categorization criterion associated with at least oneof the at least one link-quality parameter, each wireless-stationcategorization criterion comprising at least one range of link-qualityparameter values associated with a wireless-station category, theplurality of wireless-station categories defined within the AP, eachwireless-station category within the AP comprising a respectiveplurality of wireless stations associated with the AP; identifying afirst wireless-station category based, at least in part, on at least oneof the at least one wireless-station categorization criterion receivedfrom the AP and the link-quality-parameter measurement; communicatingwith the AP in accordance with a first transmission schedulecorresponding to the first wireless-station category, by refraining fromtransmitting and receiving user data during at least a first scheduledtime period of the transmission schedule, and transmitting and receivinguser data during at least a second scheduled time period of thetransmission schedule; receiving, from the AP, a request instructing theplurality of wireless stations of the first wireless-station category tomeasure interference from at least one other wireless network; measuringinterference from the at least one other wireless network to generate atleast one interference measurement according to the request; and sendingthe at least one interference measurement to the AP.
 2. The method ofclaim 1, further comprising entering a sleep mode during at least oneiteration of the first time period.
 3. The method of claim 1, furthercomprising: determining at least one adapted station-transmission powerlevel; and wherein the transmitting and receiving user data comprisestransmitting at least one user data frame to the AP at the at least oneadapted station-transmission power level.
 4. The method of claim 3,wherein the at least one adapted station-transmission power levelcomprises a station-transmission power level that is lower than a normalstation-transmission power level used when the wireless station iscommunicating with the AP in a normal mode.
 5. The method of claim 1,wherein: the plurality of wireless-station categories comprise the firstwireless-station category and a second wireless-station category, thesecond wireless-station category corresponding to a second transmissionschedule that causes a second wireless station to transmit and receiveuser data to and from the AP during at least the first scheduled timeperiod, and refrain from transmitting and receiving user data at leastduring the second scheduled time period.
 6. The method of claim 1,wherein the at least one link-quality parameter comprises at least oneof a link margin, a channel power indicator, and a signal-to-noiseindicator.
 7. The method of claim 1, wherein the plurality ofwireless-station categories are defined by non-overlapping ranges ofvalues of the at least one link-quality parameter.
 8. The method ofclaim 1, further comprising sending the link-quality-parametermeasurement to the AP, wherein the determining comprises receiving, fromthe AP, a notification specifying the first wireless-station categoryidentified for the wireless station by the AP.
 9. The method of claim 8,comprising sending a confirmation confirming the identification of thefirst wireless-station category for the wireless station to the AP inresponse to receiving the notification.
 10. The method of claim 1comprising notifying the AP of the first wireless-station categoryidentified for the wireless station.
 11. A wireless station associatedwith an access point (AP) in a wireless network, the wireless stationcomprising: a transmitting/receiving unit; and at least one processingunit communicatively coupled to the transmitting/receiving unit, the atleast one processing unit configured to: measure at least onelink-quality parameter based on at least a signal received from the APto generate a link-quality-parameter measurement; receive from the AP,via the transmitting/receiving unit, a notification comprising at leastone wireless-station categorization criterion associated with the atleast one link-quality parameter, each wireless-station categorizationcriterion comprising at least one range of link-quality parameter valuesassociated with one of a plurality of wireless-station categories, theplurality of wireless-station categories defined within the AP, eachwireless-station category within the AP comprising a respectiveplurality of wireless-stations associated with the AP; identify a firstwireless-station category based, at least in part, on at least one ofthe at least one wireless-station categorization criterion received fromthe AP and the link-quality-parameter measurement; communicate with theAP, via the transmitting/receiving unit, in accordance with a firsttransmission schedule corresponding to the first wireless-stationcategory, by refraining from transmitting and receiving user data duringat least a first scheduled time period of the transmission schedule, andtransmitting and receiving user data during at least a second scheduledtime period of the transmission schedule; receive, from the AP, arequest instructing the plurality of wireless stations of the firstwireless-station category to measure interference from at least oneother wireless network; measure interference from the at least one otherwireless network to generate at least one interference measurementaccording to the request; and send the at least one interferencemeasurement to the AP.
 12. The wireless station of claim 11, wherein theat least one processing unit is further configured to cause thetransmitting/receiving unit to enter a sleep mode during at least oneiteration of the at least one time period.
 13. The wireless station ofclaim 11, wherein the at least one processing unit is further configuredto: determine at least one adapted station-transmission power level; andcommunicate with the AP via the transmitting/receiving unit bytransmitting at least one user data frame to the AP at the at least oneadapted station-transmission power level.
 14. The wireless station ofclaim 13, wherein the at least one adapted station-transmission powerlevel comprises a station-transmission power level that is lower than anormal station-transmission power level used when the wireless stationis communicating with the AP in a normal mode.
 15. The wireless stationof claim 11, wherein: the plurality of wireless-station categoriescomprise the first wireless-station category and a secondwireless-station category, the second wireless-station categorycorresponding to a second transmission schedule that causes a secondwireless station to transmit and receive user data to and from the APduring at least the first scheduled time period, and refrain fromtransmitting and receiving user data at least during the secondscheduled time period.
 16. The wireless station of claim 11, wherein theat least one link-quality parameter comprises at least one of a linkmargin, a channel power indicator, and a signal-to-noise indicator. 17.The wireless station of claim 11, wherein the plurality ofwireless-station categories are defined by non-overlapping ranges ofvalues of the at least one link-quality parameter.
 18. The wirelessstation of claim 11, wherein the at least one processing unit is furtherconfigured to send the link-quality-parameter measurement to the AP, andreceive from the AP, via the transmitting/receiving unit, a notificationspecifying the first wireless-station category identified for thewireless station by the AP.
 19. The wireless station of claim 18,wherein the at least one processing unit is further configured to send,via the transmitting/receiving unit, a confirmation confirming theidentification of the first wireless-station category for the wirelessstation to the AP in response to receiving the notification.
 20. Thewireless station of claim 11, wherein the at least one processing unitis further configured to notify the AP, via the transmitting/receivingunit, of the first wireless-station category identified for the wirelessstation.
 21. A computer-program product comprising a non-transitorycomputer-usable medium having computer-readable program code embodiedtherein, the computer-readable program code configured, when executed byat least one processor of wireless station, to: measure, by the wirelessstation in a wireless network comprising an access point (AP) to whichthe wireless station is associated, at least one link-quality parameterbased on at least a signal received from the AP to generate alink-quality-parameter measurement; receive, from the AP, a notificationcomprising at least one wireless-station categorization criterionassociated with the at least one link-quality parameter, eachwireless-station categorization criterion comprising at least one rangeof link-quality parameter values associated with a wireless-stationcategory, the plurality of wireless-station categories defined withinthe AP, each wireless-station category comprising a respective pluralityof wireless-stations associated with the AP; identify a firstwireless-station category based, at least in part, on at least one ofthe at least one wireless-station categorization criterion received fromthe AP and the link-quality-parameter measurement; communicate with theAP in accordance with a first transmission schedule corresponding to thefirst wireless-station category, by refraining from transmitting andreceiving user data during at least a first scheduled time period of thetransmission schedule, and transmitting and receiving user data duringat least a second scheduled time period of the transmission schedule;receive, from the AP, a request instructing the plurality of wirelessstations of the first wireless-station category to measure interferencefrom at least one other wireless network; measure interference from theat least one other wireless network to generate at least oneinterference measurement according to the request; and send the at leastone interference measurement to the AP.